Sensory experience selectively reorganizes the late component of evoked responses

Abstract

AbstractIn response to sensory stimulation, the cortex exhibits an early transient response followed by a late and slower activation pattern. Recent studies suggest that the early component represents features of the stimulus while the late component is associated with stimulus perception. In this work we study how patterns of evoked and spontaneous activity are modified by experience at mesoscale level using voltage and extracellular glutamate transient recordings over widespread regions of mice dorsal neocortex. We find that repeated tactile or auditory stimulation selectively modifies the spatiotemporal patterns of activity mainly of the late evoked response. This modification lasted up to 60 minutes and results not only in an increase in amplitude of the late response after repeated stimulation, but also the spatiotemporal pattern of the late evoked activity becomes more similar to the pattern of the early evoked response. These changes occur only for the evoked responses of the sensory modality that received the repeated stimulation and they persisted up to one hour. Thus, this selective long-lasting spatiotemporal modification of the cortical activity patterns might provide new insights about how perception-related cortical activity changes with sensory experience.